In an in-train transmission control system that controls a train formation, it is important to secure the real time property of command data for controlling devices. Accordingly, techniques for securing real time property of command data in an in-train transmission control system have conventionally been proposed.
For example, Patent Literature 1 discloses a vehicle information device for electric rolling stock, which has a problem to be solve in that the device should be adapted “to achieve more real-time control and enable execution of a control function extending over vehicles for rise of vehicle performance, by lessening delay in the information transmission time as far as possible”, and “is equipped with LAN trunks (113, 213, 313, 413) which are arranged astride between vehicles of a plurality of vehicles (100, 200, 300, and 400) including a vehicle having a driver's cab, hubs (102, 202, 302, and 402) which are arranged at branch points to several apparatuses within several vehicle from several LAN trunks within several vehicles, vehicle information central devices (101 and 401) which are connected to the LAN trunks within the vehicle having driver's cabs and manage the information about each vehicle, and LAN branches (112, 212, 312, and 412) which are arranged between hubs and several apparatuses inside the vehicles within the several vehicles”. In the technique of Patent Literature 1, operation command information of a master controller, called a “mascon” in a cockpit is broadcasted simultaneously to each device in the vehicles via a hub.